`runArgs` in Dev Containers image isn't shared to `.devcontainers.json` workspace

この issue では custom-image と workspace devcontainer.json の構成が挙げられていますが、ソースファイルはありません。まず、workspace がイメージを使用する場合に runArgs がどのように読み取られ、結合されるかを追跡し、次に Docker inspect の PidMode と NetworkMode の結果を比較してください。custom-image から提供された runArgs が、それらを繰り返し指定しなくても利用側の workspace で反映されれば完了です。

Hi, I tried to use runArgs in Dev Containers custom image but this field isn't shared to .devcontainers.json workspace

• Logs :

1. when runArgs is set in Dev Containers custom image :

$ docker inspect f | grep PidMode
            "PidMode": "",    # pid isn't set to host

$ docker inspect f | grep NetworkMode
            "NetworkMode": "bridge",    # network isn't set to host

2. when runArgs is set in Dev Containers workspace that use the custom image :

$ docker inspect f | grep PidMode
            "PidMode": "host",    # pid is set to host

$ docker inspect f | grep NetworkMode
            "NetworkMode": "host",    # network is set to host

Steps to Reproduce :

1. when runArgs is set in Dev Containers custom image :

// custom image configuration
{
	"name": "Custom image",
	"build": {
		"dockerfile": "Dockerfile",
		"args": {
			"devcontainercli": "true"
		}
	},
	"runArgs": [
		"--network=host",
		"--pid=host"
	],
	"capAdd": ["ALL"],
	"securityOpt": ["seccomp=unconfined"],
	"privileged": true,
        [...]
}

// devcontainer.json workspace configuration
{
	"name": "Dev Containers demo",
	"image": "registry.example.com/example/custom-image:version",
	[...]
}

2. when runArgs is set in Dev Containers workspace that use the custom image :

// custom image configuration
{
	"name": "Custom image",
	"build": {
		"dockerfile": "Dockerfile",
		"args": {
			"devcontainercli": "true"
		}
	},
	"capAdd": ["ALL"],
	"securityOpt": ["seccomp=unconfined"],
	"privileged": true,
        [...]
}

// devcontainer.json workspace configuration
{
	"name": "Dev Containers demo",
	"image": "registry.example.com/example/custom-image:version",
	"runArgs": [
		"--network=host",
		"--pid=host"
	],
	[...]
}

Thank you !